Introduction

All nations continually face decisions involving the

supply and utilization of raw materials, substitution of one

resource for another, competing land uses, and the environmental consequences of resource development. Global

use of mineral resources will continue to increase for the

foreseeable future because of the continuing increase in

global population and the efforts to improve living standards worldwide. In today’s global economy, a nation’s

economic security depends on access to adequate mineral

resource supplies from a variety of domestic and international sources. 

No global shortages of nonfuel mineral resources are

expected in the near future; however, the growing demand

for mineral resources requires continued exploration and

development of as-yet-undiscovered mineral deposits.

Informed planning and decisions concerning sustainable

resource development require a long-term global perspective and an integrated approach to land-use, resource, and

environmental management. This integrated approach, in

turn, requires that unbiased information be available on the

global distribution of identified and especially undiscovered

mineral resources, the economic factors influencing their

development, and the environmental consequences of their

exploitation.

Focus of the Global Mineral Resource

Assessment Project (GMRAP)

In response to the growing need for minerals information,

the U.S. Geological Survey (USGS) is conducting a cooperative international project to assess the world’s undiscovered

nonfuel mineral resources, the Global Mineral Resource

Assessment Project (GMRAP). GMRAP is a research project

to develop and test methods of assessing undiscovered mineral

resources on land. The primary objectives of GMRAP are to

outline the principal land areas in the world that have potential

for selected undiscovered mineral resources and to estimate

the probable amounts of those mineral resources to a depth of

1 kilometer below the Earth’s surface.

Today, more than 70 chemical elements and dozens of

minerals are mined and produced from more than 100 different deposit types and geologic environments. GMRAP

researchers will begin by assessing a selected subset of commodities and the most significant deposit types for world

minerals supply of these commodities. This restricted focus

is designed to make the assessment effort manageable. Each

assessment will enable researchers to improve assessment

methods, geologic models, and understanding of mineral

deposit formation.

The first three commodities for which global undiscovered resources will be assessed are copper, platinum-group

metals, and potash:

• Copper was chosen because it is important in electronics

and industrial applications, it is globally distributed, and

its predictive geologic occurrence and grade-tonnage

models are well defined. The deposit types to be assessed

are porphyry copper (fig. 1) and sediment-hosted copper

deposits, which together provide about 80 percent of the

world’s copper.

• Platinum-group metals were chosen because they have

critical applications as catalysts in the automobile,

chemical, and petroleum industries; because their supply is limited and extracting them is expensive; because

only a few deposits are known globally; and because the

grade-tonnage models need to be better defined.

• Potash was chosen because it is one of the three indispensable fertilizer minerals required for food production,

because its predictive models need further development,

and because assessment methods for industrial minerals

require futher testing.

U.S. Department of the Interior

U.S. Geological Survey

USGS Fact Sheet FS–053–03

June 2003

USGS Mineral Resources Program

The Global Mineral Resource Assessment Project

Figure 1. Bingham Canyon porphyry copper deposit, Utah. The pit is

about 3 kilometers across and has produced nearly 12 million tons of

copper since it opened in 1904. Photograph by Charles Cunningham,

U.S. Geological Survey.
In all, undiscovered resources of 8 commodities will be

assessed during the 8 years of GMRAP:

Metals Industrial minerals

copper phosphate (phosphorus source)

gold potash (potassium source)

lead

nickel

platinum-group metals

zinc

USGS Three-Part Form of Assessment

A quantitative form of resource assessment is required to

express explicitly the degree of uncertainty associated with

assessments and to allow economic analysis that can translate

geology-based results into a format usable in decision-support

systems and cost-benefit analysis. Quantitative assessment

results are essential for the effective evaluation of the consequences of alternative resource-related decisions. The USGS

has developed a three-part form of quantitative mineral

resource assessment to meet these goals (fig. 2). Three-part

assessments consist of the following (Singer, 1993):

1. Delineating areas permissive for undiscovered mineral

resources according to the types of deposits permitted by

the geology

2. Estimating the number of undiscovered deposits of each

type for each delineated area

3. Estimating the amount of resources contained in the

undiscovered deposits by using appropriate ore characteristics and metal contents defined by worldwide grade

and tonnage models

The three-part quantitative assessment results in internally

consistent quantitative estimates of undiscovered mineral

resources. The assessment results can be evaluated by using

economic filters, cash-flow models, and other tools for application to economic, environmental, and policy analysis (fig. 2).

The USGS is improving mineral deposit models and resource

assessment methods (for example, Singer and others, 2001).

Figure 2. The U.S. Geological Survey’s three-part form of quantitative mineral resource assessment. The three elements on the left show that

geologic data are used to delineate areas permissive for undiscovered mineral resources, to estimate the number of undiscovered deposits,

and to estimate the amount of resources that they contain. Resource, economic, and policy analysis tools are shown in the center of the figure.

On the right are assessment results for the potential mineral supply and environmental, land-use, and economic planning.
Use of Global Mineral Resource

Assessment Results

An example of how results from a global mineral

resource assessment could be used to help evaluate tradeoffs associated with minerals development is illustrated in

figure 3, showing hypothetical mineral resource assessment tracts overlain on a map of global biodiversity. Mining in high latitudes, where biodiversity is low, such as in

the tract in northern Canada, probably will have a smaller

impact on biodiversity than mining in low latitudes where

biodiversity is much greater, such as in the tract in central

Africa. In addition, without mining, many of the high-latitude areas have little or no employment and infrastructure and, unlike in the tropics, subsistence farming is difficult or impossible.

On the other hand, disturbed ecosystems in high latitudes would likely require a longer time to recover from the

effects of development than those at lower latitudes. Infrastructure development that follows mining into remote

regions can disrupt sensitive habitats. In order to reduce

habitat fragmentation in remote regions, information from

a global assessment could help efforts to encourage mineral

exploration and development in identified regions of mineral

potential where infrastructure already exists.

GMRAP Schedule

GMRAP is currently an 8-year project begun in 2002.

The first priority for the project has been identifying and

formalizing relations with cooperators from countries and

multinational organizations in seven designated assessment

regions (fig. 4). In addition, reports are being written containing overviews of regional geology, recent exploration,

significant known mines and mineral resources, major past

and current production, and supply-demand relations.

GMRAP researchers aim to complete compilation of available geologic information and creation of databases of

known mineral deposits and exploration history for each

region by the mid-point of the project. Subsequently, assessments for undiscovered copper, gold, lead, nickel, platinumgroup metals, zinc, phosphate, and potash will be completed; the results will be published for each commodity as

completed in digital, Web-based, and paper formats, as

appropriate.

Large

Medium

Small

Figure 3. A conceptual global assessment in which tracts predicted to contain undiscovered deposits of a hypothetical nonfuel mineral

resource are shown overlying a map of species diversity for vascular plants. The base map of biodiversity is online at

http://www.botanik.uni-bonn.de/biodiv/phytodiv.htm and is modified from Barthlott and others (1999).
A Cooperative International Project

GMRAP is being conducted on a regional, multinational

basis with the cooperative participation of interested national

and international geologic, mineral resource, and other institutions (see box). All assessment products will be published by

the USGS in conjunction with the international cooperators.

The USGS role also includes the following:

• Coordinating the global assessment

• Facilitating workshops and working group meetings

• Compiling regional products into a global mineral

resource assessment

• Analyzing assessment results with regard to regional and

global resource, land-use, and environmental issues

• Leading quantitative probabilistic estimation of undiscovered nonfuel mineral deposits

The role of international cooperators includes the

following:

• Providing access to and translation of existing geologic

maps at appropriate assessment scales (1:1,000,000 or

smaller). Emphasis will be on establishing regional consistency in geologic interpretation and on estimating the

extent of buried geologic units permissive for undiscovered mineral deposits.

• Contributing to development of databases of current

information on the location, sizes, and geologic types of

significant known mineral deposits and occurrences

• Providing information about regional mineral exploration

history

• Reviewing quantitative mineral resource assessment

products

• Assisting in the analysis of assessment results

Conclusion

GMRAP will provide a consistent, comprehensive level of

information and analysis of global nonfuel mineral resources

based on the newest data available. The assessment results will

provide all nations with a regional and global context for—

• Evaluating their known and undiscovered nonfuel mineral

resources

• Designing new mineral exploration

• Planning sustainable resource development

• Anticipating environmental problems

• Making land-use decisions

References Cited

Barthlott, W., Biedinger, N., Braun, G., Feig, F., Kier, G., and

Mutke, J., 1999, Terminological and methodological

aspects of the mapping and analysis of global biodiversity:

Acta Botanica Fennica, v. 162, p. 103–110.

Singer, D.A., 1993, Basic concepts in three-part quantitative

assessments of undiscovered mineral resources: Nonrenewable Resources, v. 2, no. 2, p. 69–81.

Singer, D.A., Menzie, W.D., Sutphin, D.M., Mosier, D.L.,

and Bliss, J.D., 2001, Mineral deposit density—An

update, chapter A of Schulz, K.J., ed., Contributions to

global mineral resource assessment research: U.S. Geological Survey Professional Paper 1640, p. A1–A13.

(Also available online at

http://pubs.usgs.gov/prof/p1640a/.)

For further information, please contact:

Klaus J. Schulz

Joseph A. Briskey

U.S. Geological Survey

MS 954, National Center

12201 Sunrise Valley Drive

Reston, VA 20192

E-mail: kschulz@usgs.gov

jbriskey@usgs.gov

Figure 4. The seven assessment regions for the Global Mineral

Resource Assessment Project (GMRAP) are shown by different

colors.

Some Major GMRAP Cooperators

• Asociación de Servicios Geológicos y Mineros de Ibero

América (represents geological surveys of South America)

• Bureau de Recherches Géologiques et Minières (BRGM),

France

• Centre for Russian and Central Asian Mineral Studies

(CERCAMS), Natural History Museum, London

• China Academy of Geological Sciences

• China Geological Survey

• Coordinating Committee for Geoscience Programmes in East

and Southeast Asia (CCOP) (represents geological surveys of

Cambodia, China, Indonesia, Japan, Malaysia, Papua New

Guinea, The Philippines, Republic of Korea, Singapore,

Thailand, Vietnam)

• General Directorate of Mineral Research and Exploration

(MTA), Republic of Turkey

• Geological Institute of the Academy of Sciences, Republic of

Georgia

• Geological Survey of Canada

• Geological Survey of Japan (part of the National Institute of

Advanced Industrial Science and Technology, AIST)

• Institute of Geology and Mineral Resources (IGMR),

Mongolian Academy of Sciences

• Instituto Geológico Minero y Metalúrgico (INGEMMET),

Peru

• International Union of Geological Sciences and UNESCO

Deposit Modeling Program

• Korea Institute of Geoscience and Mineral Resources

• Russian Academy of Sciences

• Servicio Nacional de Geología y Minería (SERNAGEOMIN),

Chile

• Society of Economic Geologists

• University of Arizona